/*
 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
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 *
 *
 *
 *
 *
 *
 *
 */

package javax.tools;

import java.io.*;
import java.net.URI;
import java.nio.CharBuffer;
import javax.lang.model.element.Modifier;
import javax.lang.model.element.NestingKind;
import javax.tools.JavaFileObject.Kind;

/**
 * Provides simple implementations for most methods in JavaFileObject.
 * This class is designed to be subclassed and used as a basis for
 * JavaFileObject implementations.  Subclasses can override the
 * implementation and specification of any method of this class as
 * long as the general contract of JavaFileObject is obeyed.
 *
 * @author Peter von der Ah&eacute;
 * @since 1.6
 */
public class SimpleJavaFileObject implements JavaFileObject {

  /**
   * A URI for this file object.
   */
  protected final URI uri;

  /**
   * The kind of this file object.
   */
  protected final Kind kind;

  /**
   * Construct a SimpleJavaFileObject of the given kind and with the
   * given URI.
   *
   * @param uri the URI for this file object
   * @param kind the kind of this file object
   */
  protected SimpleJavaFileObject(URI uri, Kind kind) {
    // null checks
    uri.getClass();
    kind.getClass();
    if (uri.getPath() == null) {
      throw new IllegalArgumentException("URI must have a path: " + uri);
    }
    this.uri = uri;
    this.kind = kind;
  }

  public URI toUri() {
    return uri;
  }

  public String getName() {
    return toUri().getPath();
  }

  /**
   * This implementation always throws {@linkplain
   * UnsupportedOperationException}.  Subclasses can change this
   * behavior as long as the contract of {@link FileObject} is
   * obeyed.
   */
  public InputStream openInputStream() throws IOException {
    throw new UnsupportedOperationException();
  }

  /**
   * This implementation always throws {@linkplain
   * UnsupportedOperationException}.  Subclasses can change this
   * behavior as long as the contract of {@link FileObject} is
   * obeyed.
   */
  public OutputStream openOutputStream() throws IOException {
    throw new UnsupportedOperationException();
  }

  /**
   * Wraps the result of {@linkplain #getCharContent} in a Reader.
   * Subclasses can change this behavior as long as the contract of
   * {@link FileObject} is obeyed.
   *
   * @param ignoreEncodingErrors {@inheritDoc}
   * @return a Reader wrapping the result of getCharContent
   * @throws IllegalStateException {@inheritDoc}
   * @throws UnsupportedOperationException {@inheritDoc}
   * @throws IOException {@inheritDoc}
   */
  public Reader openReader(boolean ignoreEncodingErrors) throws IOException {
    CharSequence charContent = getCharContent(ignoreEncodingErrors);
    if (charContent == null) {
      throw new UnsupportedOperationException();
    }
    if (charContent instanceof CharBuffer) {
      CharBuffer buffer = (CharBuffer) charContent;
      if (buffer.hasArray()) {
        return new CharArrayReader(buffer.array());
      }
    }
    return new StringReader(charContent.toString());
  }

  /**
   * This implementation always throws {@linkplain
   * UnsupportedOperationException}.  Subclasses can change this
   * behavior as long as the contract of {@link FileObject} is
   * obeyed.
   */
  public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {
    throw new UnsupportedOperationException();
  }

  /**
   * Wraps the result of openOutputStream in a Writer.  Subclasses
   * can change this behavior as long as the contract of {@link
   * FileObject} is obeyed.
   *
   * @return a Writer wrapping the result of openOutputStream
   * @throws IllegalStateException {@inheritDoc}
   * @throws UnsupportedOperationException {@inheritDoc}
   * @throws IOException {@inheritDoc}
   */
  public Writer openWriter() throws IOException {
    return new OutputStreamWriter(openOutputStream());
  }

  /**
   * This implementation returns {@code 0L}.  Subclasses can change
   * this behavior as long as the contract of {@link FileObject} is
   * obeyed.
   *
   * @return {@code 0L}
   */
  public long getLastModified() {
    return 0L;
  }

  /**
   * This implementation does nothing.  Subclasses can change this
   * behavior as long as the contract of {@link FileObject} is
   * obeyed.
   *
   * @return {@code false}
   */
  public boolean delete() {
    return false;
  }

  /**
   * @return {@code this.kind}
   */
  public Kind getKind() {
    return kind;
  }

  /**
   * This implementation compares the path of its URI to the given
   * simple name.  This method returns true if the given kind is
   * equal to the kind of this object, and if the path is equal to
   * {@code simpleName + kind.extension} or if it ends with {@code
   * "/" + simpleName + kind.extension}.
   *
   * <p>This method calls {@link #getKind} and {@link #toUri} and
   * does not access the fields {@link #uri} and {@link #kind}
   * directly.
   *
   * <p>Subclasses can change this behavior as long as the contract
   * of {@link JavaFileObject} is obeyed.
   */
  public boolean isNameCompatible(String simpleName, Kind kind) {
    String baseName = simpleName + kind.extension;
    return kind.equals(getKind())
        && (baseName.equals(toUri().getPath())
        || toUri().getPath().endsWith("/" + baseName));
  }

  /**
   * This implementation returns {@code null}.  Subclasses can
   * change this behavior as long as the contract of
   * {@link JavaFileObject} is obeyed.
   */
  public NestingKind getNestingKind() {
    return null;
  }

  /**
   * This implementation returns {@code null}.  Subclasses can
   * change this behavior as long as the contract of
   * {@link JavaFileObject} is obeyed.
   */
  public Modifier getAccessLevel() {
    return null;
  }

  @Override
  public String toString() {
    return getClass().getName() + "[" + toUri() + "]";
  }
}
